Section Titles and Cell Formatting

Use formatting commands to add in section headings, problem statements, and notes to your workbooks. The easiest way to do this is to highlight a cell (click on the bracket on the righthand side of the window) and then hit Alt+1, Alt+2, etc. I cycle through these until I find what I want.

A common error when calculating partial derivatives at a point is to define "f[x_,y_]:=" and then (assuming for now (x,y)=(1,2)) to try "$\partial$xf[1,2]". This doesn't work! Mathematica evaluates "f[1,2]" first and then takes the derivative, so the value is ALWAYS 0. Instead, type "$\partial$xf[x,y]/.{x->1,y->2}". Alternately, you can define "fx[x_,y_]:=$\partial$xf[x,y]" and then type "fx[1,2]".